The present invention relates to spray-chilled nabumetone and a process for its manufacture.
GB 1,474,377 describes a non-steroidal anti-inflammatory drug 4-(6-methoxy-2-naphthyl)-butan-2-one which is Commonly known as nabumetone. This patent also describes a process for the manufacture of nabumetone.
Nabumetone is most commonly prescribed as 500 mg or 1000 mg swallow tablets. The resulting tablets containing nabumetone and conventional excipients are fairly large in size and can be a problem to swallow for some patients.
Conventionally isolated and milled nabumetone has a poured density range of 0.35 to 0.39 gcm.sup.-3 and a tapped density range of 0.44 to 0.48 gcm.sup.-3 and when mixed with conventional excipients produces a tablet volume of 0.485 cm.sup.3 for a 500 mg nabumetone tablet and a volume of 0.970 cm.sup.3 for a 1000 mg nabumetone tablet.
Conventionally isolated and milled nabumetone is formulated into conventional swallow tablets by admixing with conventional fillers, surfactants and disintegrants. It has been found that the maximum amount of drug that can be mixed with excipients, especially fillers, is 82%. Increasing the percentage of drug further (i.e. reducing the percentage of excipients, especially fillers) causes the tablet to be prone to breaking up on manufacture, storage and transportation, which is obviously a disadvantage.
Spray-chilling is a technique that has been in existence for approximately 30 years, and has been applied to the production of food-stuffs such as coffee as well as pharmaceuticals.
Spray-chilling is usually chosen because it is a process which produces uniform product qualifies such as particle size, moisture content and bulk density.
In pharmaceutical production, spray-chilling is used because it can provide products which have improved flow characteristics.